How can I create a simple 4x3 two dimensional array in Java?

Question

I've got it down in C++, but Java is proving more challenging to me. Here's what i have. I simply want it to have 4 rows and 3 columns initialized to 1-12 and to print it to the screen. Are my errors apparent to you? Thanks!

I get 13 errors :(

including line9:twoDArray[][] not a statement, ; expected, illegal start of expression, all a few times each.

Code i tried:

import java.util.*;


class twoDimensional array
{ public static void main(String args[])
{
int[][] twoDArray = new int[4][3];

twoDArray[][]={{1,2,3},{4,5,6},{7,8,9},{10,11,12}};

System.out.print(twoDArray.toString);


}
}

Pl add your original post and for this splitting please create separate question. — Rajen Raiyarela, Feb 26 '16 at 06:35
I would but I deleted the original context. I won't again, sorry. — Ben, Feb 26 '16 at 06:38
I added back original question text, pl accept edit and create another question. — Rajen Raiyarela, Feb 26 '16 at 06:47

score 5 · Accepted Answer · answered Feb 26 '16 at 06:05

5

First, arrays (even 2d arrays) don't override Object.toString. You can use Arrays.deepToString(Object[]) and initialize your array when you declare it. Something like

int[][] twoDArray = new int[][] { 
        { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 }, { 10, 11, 12 } 
};
System.out.println(Arrays.deepToString(twoDArray));

answered Feb 26 '16 at 06:05

Elliott Frisch

198,278
20
158
249

1

Thank a lot! Arrays.deepToString() huh.. I learned something new! – Ben Feb 26 '16 at 06:17

score 1 · Answer 2 · answered Feb 26 '16 at 06:08

1

Have modified your code

import java.util.*;

class twoDimensional array
{ 
    public static void main(String args[]){
      int[][] twoDArray = {{1,2,3},{4,5,6},{7,8,9},{10,11,12}};
      //For printing array you have to do 
      System.out.print(Arrays.deepToString(twoDArray));
    }
}

answered Feb 26 '16 at 06:08

Rajen Raiyarela

5,526
4
21
41

Thanks a bunch buddy! – Ben Feb 26 '16 at 06:18

score 1 · Answer 3 · answered Feb 26 '16 at 06:11

1

import java.util.*;

class twoDimensionalArray
{ 
public static void main(String args[])
{
int[][] twoDArray = new int[][] { 
    { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 }, { 10, 11, 12 } 
};
System.out.println(Arrays.deepToString(twoDArray));
}
}

answered Feb 26 '16 at 06:11

Anurag Goel

468
10
15

2

Thank a lot! Arrays.deepToString() huh.. I learned something new! Appreciated. – Ben Feb 26 '16 at 06:18

score 0 · Answer 4 · answered Feb 26 '16 at 06:17

0

Here Is The Full Working Copy

public class TwoD {

public static void main(String... args)
{
    int [][]twoD = new int[4][3];
    int num = 1;

    for(int i = 0; i < 4; i++)
    {
        for(int j = 0; j < 3; j++)
        {
            twoD[i][j] = num;
            num++;
        }
    }

    for(int i = 0; i < 4; i++)
    {
        for(int j = 0; j < 3; j++)
        {
            System.out.print(twoD[i][j]+"\t");
        }
        System.out.println("");
    }
}

}

answered Feb 26 '16 at 06:17

Abhishek

3,348
3
15
34

Thanks! Could you help me out with it now that I've edited my question? – Ben Feb 26 '16 at 06:45
yes because array initialization is not allowed in that case – Abhishek Feb 26 '16 at 08:07

How can I create a simple 4x3 two dimensional array in Java?

4 Answers4